Author : Seema Mittal, M.P. Dave and Anil Kumar

The position control of a standard robotic arm under faults has been studied and the performance is compared using a combination of several control approaches. The manipulator of a robot is exposed to possible faults and combinations of control techniques are employed. Here, several control combinations of PID along with optimal and robust techniques such as LQR, H2, H∞ and H∞-static output feedback (SOPF) controls have been designed. The control gains have been obtained offline using equivalent linearization of the robot dynamic system. The hybrid controls are implemented online on PUMA 560 robot. The relative efficiency has been obtained using H2- control augmented with PID. The proposed hybrid control approach has been successfully implemented on six degree of freedom robot accommodating common types of faults represented as an exponential function, sudden or abrupt in nature.

Keywords: Fault-tolerant control, PUMA robot, hybrid control, PID, LQR, H2 control, H∞ control, performance of robot.

Article published in International Journal of Current Engineering and Technology, Vol.6, No.5 (Oct-2016)